looking for tips. Heater not working

[Elk Hunter]

I have a 1986 chevy wrangler. my problem is the fan for my heater and ac is not working. I have tested the motor, its good, replaced switch, and relay. Fuse is good, resistor looks good. Not sure what the problem is. What am i missing???????

 

[tex78]

Ground to the motor ???

Resistor can look good but has a diode built into it that opens and the no power goes through.

Do u have power on the purple wire and ground on the black ( ground wire goes the outer bolts that hold the motor in and can get a bad connection there )



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[Highfly]

Do some of the fan speeds work and not others? Classic sign of Resistor. Grab a light tester and start probing.

 

[Ancient Sledder]

If I remember correctly, there is a wiring harness junction block near the glove box hinge. It will be burned in the plug.

 

[tex78]

But a 86 has the blower on the engine side of the fire wall , and if mem serves the wires go through the body plug at the drivers side.

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[Elk Hunter]

There is no fan speeds at all. I changed the relay. There is power to the relay but no power to the purple wire that goes to the fan. Would there be an inline fuse that im missing?I will have a look behind the glove box and see if there is a junction box there. The wires do come into the cab in that area.

 

[tex78]

Ok but do u have ground to the motor ??
And then the blower resistor pack ( mounted beside the blower with like 4 wires and a square block.

Look for power into it and out of it.


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[Elk Hunter]

Yes the motor is grounded and there is power going into the relay but nothing coming out. I have tested the relay and resistor in another truck and they work fine.

 

[Elk Hunter]

No power in or out of resistor

 

[Highfly]

No power in or out of resistor

What about the switch it's self on the heater control? Did you check it? Since you have access to a similar truck use it to probe for power. Find out what wires have power and when. Then cross reference that over to your truck.

Edit, sorry just reread your first post and you have replaced the switch....